[unreadable] The current study proposes to investigate the relationship between anxiety and heroin use. Previous work has identified that heroin users evidence increased levels of anxiety sensitivity, defined as the fear of anxiety and anxiety-related sensations (Lejuez et at, 2004), which may place them at an increased risk for initial heroin use, continued use, and high relapse rates during treatment efforts. This study will examine AS, prevalence rates of anxiety psychopathology, as well as levels of symptomatology of components of anxiety (e.g., social anxiety, panic, state/trait anxiety) within a sample of 140 inner-city treatment seeking drug users compared across (1) primary heroin users with no crack/cocaine use (n = 35), (2) primary crack/cocaine users with no heroin use (n = 35), (3) individuals who use both heroin and crack/cocaine (n = 35), and (4) individuals dependent on either alcohol, marijuana, or hallucinagens (including PCP) with no use of heroin and crack/cocaine (n = 35). Results of this study will aid in identifying potential anxiety vulnerabilities in drug users, particularly heroin users, and set the stage for future work explicating the direction of the observed associations. [unreadable] [unreadable] [unreadable] [unreadable]